Speed control for internalcombustion engines



June 21, 1949. M. MALLORY 2,473,762

SPEED CONTROL FOR INTERNAL-COMBUSTION ENGINES Filed Sept. 25, 1947INVENTOR. Mfl/IOI? Mad/org BY I v Patented June 21, 1949 SPEED CONTROLFORINTERNAL- COMBUSTION ENGINES Marion Mallory, Detroit, Mich., assignorto The Mallory Research Company, Detroit, Mich., a corporation ofMichigan A Application September 25, 1941, Serial No. 176,114

This invention relates to means for stopping or slowing down the runningof an internal combustion engine when a predetermined speed has beenattained. I v

It has heretofore been the practice to control the speed of'internalcombustionengines by speed governors which actuated the carburetorthrottle or a central throttle to reduce the fuel supply to the enginewhen a predetermined speed has beenreached. This form of control isobjected to by automobile fleet owners for the reason that thehorsepower of the engine is reduced before the speed limit isreached,whereas it is desiredto maintain the full horsepower right up to thepoint where the permissible engine speed is reached.

The object. of the present invention is to obviate this objection to theuse of speed control governors for internal combustion engines by theprovision of means in connection with the carburetor that isautomatically actuated to completely stop the flow of fuel to thecarburetorthroat, when, and not until, a predetermined engine speed hasbeen reached so that full engine horsepower is maintained right-up tothe engine speed limit desired. a

The invention is fully described in the following specification and oneembodiment thereof illustrated in the accompanying drawing,'which'is acentral longitudinal section of an apparatus embodying the inventionwith parts in full and with both the fuel feed control valve andtheairvent control valve open.

Referring to the drawings, I designates a carburetor casing forming afuel feed throat or passageway 2 to an associated engine (not shown) andhaving the customary venturi restriction 3 therein. Inward from thisrestriction is the customary throttle valve d. A fuel feed nozzle isprojected into the fuel feed passageway 2 adjacent to the inlet end ofthe restriction 1 Claims. (oi zs -iosi the fuel mixture through thepassageway 2 to the engine cylinders during the running of the enginewill create a suction-in said channel [4 and chamber I3, tending to drawthe diaphragm 12 outward. This movement of the diaphragm draws the valveI ll outward against the seat 9 and stops the. flow offuel to the nozzle5 and also to the ,idler Jets l5 which are fed through a channel Hi fromthe nozzle channel 6.

- .The-suction tube also has that is normally open to the atmospherethrough a vent opening l8 that is controlled by a nor- 3 and the channel6 of this nozzleextends into I the carburetor fuel bowl I and isprovided therein with a valve casing 8 having an internal valve seat 9therein. A valve llioperates in the casin and seats outwardly againstthe seat 9 to close the bowl communication with the nozzle tube orchannel 6.

The stem H of the valve Ill is attached to a diaphragm l2 in a suctionchamber l3and normally holds the valve in open position. The outer sideof this diaphragm is subjected to suction from the interior of thepassageway 2 ,to the engine at the engine side of the throttle valve 4 Jmally open cent'zifug'aliy operated governor valve i9.- Itls thusapparent that the relief valve i9 is normally open so that bleeding ofthe suction line occurs and the carburetor valve i0 is permitted toremain open until the engine reaches a predetermined speed. When thisoccurs, the relief valve it closes and suction is built up inthe chamberi3 to draw the carburetor valve in into engagement with the seat 9 andto stop the fuel feed to the carburetor nozzle.

The governor 20 which controls the closing of the vent l8 has arotatable member 21 driven by the engine and has the vent opening l8therein to which a vent passage 22 leads. The passage 22 is providedwithin said member with a' valve chamberin which the weighted portion ofthe valve l9 operates, and the outer end of this chamber is providedwith ventopening i8- Thevalve i9 is normally held in inwardly retractedopen position by a spring 23'tensloned to permit the valve to moveoutward and close the vent opening when a predetermined engine speed hasbeen reached. A tension adjusting screw 24 is mounted in the member 2iand connected to the spring.

It is apparent that under normal operating conditions of the enginebelow a speed of say 3;000 R. P. M., the vent valve 19 remains open soas to bleed the suctionchannel it and the suction side of the chamberl3. This permits the diaphragm l2 in said chamber to remain in normalposition with the carburetor valve Ill open. When the engine speedreaches the speed limit at which the governor spring 23 is set, thevalve I9 will move outward by centrifugal; action and close the ventopening l8. This stops the admission of atmospheric air to the suctionpassages i4 and I! and the chamber I3 so that suction quickly.

. builds up in the chamber-l3 suflicient to draw the valve ill to itsseat 9, thereby closing thepassage 6 to the main and idlerjets 5 and I5of the carburetor and completelystopping the flow of through a tubeorchannel It so that the rush of 66 fuel therethrough.

a vent'passage ll asvavea 3 It is apparent that with this control, fullhorsepower operation of the engine is possible right up to the pointwhere the engine checking speed i is reached, which is an importantfeature.

Upon a stoppage of the fuel flow to and from the main and idler feedorifices, the fuel that had gone into the engine would all be, burnedand there would be no fuel in the muilier to cause backfire orexplosions. The engine would'simply quit or slow down every time theoperator tried to overspeed, the same as if he ran out of gasoline, butthere would be no eflect whatever on the power below the limit speed.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerous modifications and changes without departing from the spirit ofthe claims. Having thus described my invention, what claim as new anddesire to secure by United States Letters Patent is:'

l. The combination with aninternal combus-' .4 wherein said last meanscomprises a relief channel in communication with said valve closingmeans, a normally open relief valve for closing said relief channel, andmeans rotatably driven by the engine and carrying said relief valve tocause it to act by centrifugal action to close the relief channel whenthe engine reaches a predetermined open throttle speed.

4. The combination with an internal combustion engine having a fuel feedpassageway to its cylinders and a carburetor for feeding fuel to saidpassageway and comprising a fuel supply source and one or more nozzlelets having their channels in communication with said source and throughwhich fuel is drawn by suction action in thepassageway, of a normallyopen valve for closing said channel. a suction chamber havingcommunication with said passageway, a diaphragm in said chamberconnected to said valve tion engine having a fuel feed passageway to 1its cylinders, and a carburetor for feeding fuel to said passageway andcomprising a fuel supply source, a main nozzle orifice opening into thepassageway with a channel communicating with said source and throughwhich fuel is drawn to said orifice by suction action in the passageway,and a throttle at the suction side of said nozzle, of a valve forclosing said channel and normally standing in open position, and meansoperable by suction action in said passageway and by engine speed toclose said valve and stop the fuel flow to the nozzle when the enginehas reached a predetermined open throttle speed.

2. The combination with an internal combustion engine having a fuel feedpassageway,

to its cylinders and a carburetor for feeding fuel and operable bysuction in the passageway to close said valve, and means operableby theengine to relieve the valve closing suction action on the diaphragmuntil the engine reaches a predetermined open throttle speed.

5. The combination as called for in claim 4 wherein said last meansincludes a centrifugally operated valve for closing a relief from saidchamber when a predetermined engine speed is reached. I

6. The combination with an internal combustion engine having acarburetor with a fuel bowl and a nozzle with its channel incommunication with said bowl and through which fuel is drawn to theengine by suction action, of a normally open valve movable to close saidchannel, means operable by an engin created suction action to close saidvalve, and means operable by the ensine for preventing said last meansto act to close the valve until the engine has reached a predeto saidpassageway and comprising a, fuel suppl 40 termm-ed speed bowl and anozzle orifice into the passageway from said bowl with a channelcommunicating therewith and through which fuel is drawn by suctionaction in the passageway, of a valve for closing said channel andnormally standing in open position, means connected to said valve andoperable by suction action in said passageway to close said valve andstop the flow of fuel. in the nozzle, and means operated by the enginefor preventing said last means from acting to 50 close the valve shortof a predetermined speed of the engine.

31 The combination as called for in claim 2 MARION MALLORY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number

